Raynaud's phenomenon is thought to occur when, in response to cold or emotional stress, there is closure of the digital arteries and cutaneous arterioles leading to the clinical finding of sharp demarcated digital pallor and cyanosis of the distal skin of the fingers and/or toes. Patients often continue to experience problems despite current available treatment. Our study will investigate the use of a new vasodilator called Fasudil, a Rho-kinase inhibitor. Our hypothesis is that Fasudil will prevent vasoconstriction of digital and cutaneous arteries during a standard laboratory based cold exposure and will therefore improve digital blood flow and skin temperature recovery time following cold challenge. These data will provide the rationale for a more elaborate clinical trials in real life situations.